Nothing fancy on this end– I added the .kext to the kext folder, opened my opencore config with ProperTree and did the "Shift + R" key combo which searches your opencore folder for any changes or added kexts, etc and automatigically adds them. Then booted and voila!
That said– here is a copy/paste directly from my config file if it helps:
XML:
<array>
<dict>
<key>BundlePath</key>
<string>CommanderProFix.kext</string>
<key>Comment</key>
<string></string>
<key>Enabled</key>
<true/>
<key>ExecutablePath</key>
<string>Contents/MacOS/CommanderProFix</string>
<key>Arch</key>
<string>Any</string>
<key>MaxKernel</key>
<string></string>
<key>MinKernel</key>
<string></string>
<key>PlistPath</key>
<string>Contents/Info.plist</string>
</dict>
</array>